Pneumatic pad for cassettes



Aug. 1s, 1925.

A. w. BUCK PNEUMATIC PAD FORl CASSETTES Filed J 1y 22. 1924 Patented Aug. 18, 1925*.

yufr:urso stares i. wrt

rarer-ii ARTHUR W. BUCK, 0F ST. LOUIS, lVISSOUR.

PNEUMATIC PAD FOR'GASSETTES.

Application led July' 22,

To all whom t may concern.'

yBe it known that I, ARTHUR W. BUCK, a

-citizen of the United States, residing at St. Louis, in the county oSt. Louis and State of lvlissouri, have invented certaininew and useful improvements in Pneumatic Pads for Cassettescff which the following,` is a specification, ,reference being lhad to the accompanying drawings.

This invention relatestoY-cassettes'such as are used in taking `X-raypictures, and `particularly-to a pad `for use in connection with such a cassette as that illustrated in my pending,l application Serial #5M-,728, tiled on the 31st day'o'f May, 1922.

The ordinary cassette is formed ot a more or less rectangular frame havingsheet aluminum or material citan equivalent character stretched tightly across the frame vtormingthe front of the cassette. The back ot the cassette is hinged'to the front and consists oi' a relatively .stilil plate Ot aluminum or other suitable material which vsets into the rectangular ytrame. The back is `ordinarily lined with telt so as to secure .aclose contact of the iilm against the iront offthe cassette. Y

In the taking of X-ray pictures by means of these cassettes, 'intensifying screens are often used and it becomes `particularly necessary, `Where these intensifying screens are used and Where Potter-Bucky diaphragme are used, that special means be provided for holding the screens in close contact over their entire .surface with the X-ray film. it Was yimpossible to secure this close' contact With the use of felt and, therefore, pneumatic pads were designed for this purpose. These lpneumatic pads, however, were simply inserted between the back of the cassette and the film or intensifying screen and it was diiicult to properly iniiate these pads so as to secure close contact or to so dispose the pad that `it would secure proper contact over the entire suri'ace of the `-fluorescent screen and ilm. K

In order to avoid these diiticulties, it Was necessary to provide means whereby the pad could be permanently attached) to the inside of the back, and to this end I tried gluingl the rubberpad to the inside of the cassettel cover, but yI 4found that this was not at all practical. This is a diiiicult thing to do, and furthermore as the cassette is opened and closed the air travels from one end of the pad to the other and produces a crawl- 1924. Serial' No. 72?,532.

ing movement which Will .sooner or later causethe pad to become detached from the cassette cover.

lln order to avoid this', I provide a Spad having` iioii-intiatable extensions which are permanently attached Ato the back so that the pad .is always attacliedto the back of, the cassette frame. Such an extension greatly assists in holding the pad in position, but preferably l provide a plurality of extensions i'romthc margin or' the pneumatic pad which vviil engage with the bach ot the cassette, and provide means whereby the pneumaticv pad may be inflat d through an openin the bach ci the cassette. N

My invent-ion is illustrated in the accompanying drawing, wherein:-

Figure i is a rear elevation et a cassette constructed in accordance with 'my invention:

Figure il is an enlargedsection on thc line 2-2 oit lfigure l;

Figure 3 is a perspective view of the rubber pad and extensions;

Figure t is a perspective View of `the telt sheet or covering;

Figure 5 is a perspective view oli-a slightly niodiiied form of pad;

' Referring); to these draivingsfit will 'be .seen that vthe cassette is ot the usual forni and comprises the rectangular 'tram-e l0, the trent sheet il, and the back l2. As .tar as the present invention goes, l do not Wish to be limited to any particular torni or con struction Y.tor the back and 'liront of the cassette. The back is illust-rated as hinged at lil to the iront. This ifranie and the bachr and t'ront are preferably constructed ot sheet aluminum. The frame i() is provided at intervals with keepers lll. and the back lf2 is provided 'with spring' latches 15 engagea-ble Vith said keepers. Preferably a pneumatic. pad is used. rihere arefthree sets ot these keepers and three springs 15.

rlhe pneun'iatic pad consists of tivo sheets ot rubber 16 and l? which are attached at their margins in any suitable manner and, oit'. course, vulcanized so as to be air-tight, and the middleot one oill these sheets ris provided rWith the outwardly projecting' nipple i8 which extends through the back and is provided with an air valve 19 such as is used on a penumatic tire. Projecting from the margins ot the pneumatic pad are a plurality of tabs or extensions 20. Preferably there are tour of these extensions, one eX- tending from each side edge olf the pad, and preferably, though not necessarily, these extensions are brought around to the outside of the back, as shown in Figure 2, and are fastened by means et' screws, rivets or any other suitable means, designated generally 21. This means may be such as will permit the detachment oit the pad in case it becomes worn and permit the replacement of the worn pad by a new pad, or the means may be permanent. These extensions or tabs are of relatively thin material so that they form no practical impediment to the insertion ot the back within the 'trame 10. Preferably a telt or cloth covering, which is designated 22, extends over the inner face o1 the pad and preferably the margins of this covering are brought around the edges of the back and over upon the outside thereof and are held in pace by metallic strips 23 These metallic strips 23 are riveted, screwed or otherv-.fise attached to the iframe by the screws 2l. and extend over the margins ot the gt'elt and over the projecting tabs.

As betere remarked, l do not wish to be limited to the particular number oi" tabs or extensions, nor to these extensions having the particular form shown in Figure 3, as it is obvious that the extension might be in the form out a thin strip extending around the entire margin oit the back, as illustrated in Figure 5 and designated 20@ ln any case, the penulnatie pad is held it'roin any .movement A pneumatic pad constructed in accordance with my invention requires but very little inflation, the pressure on the screen being obtained when the cover is closed,

thereby pressing the pad against the screen. On account oit the smallv amount oit inflation necessary, the pad is always limber, having no particular shape, and this is the reason why it must be held to the cover ot the cassette in some manner which will prevent its wadding or curling up. This prevention of wedding or curling up is secured by attaching the penumatic pad to the cover or bach by means ol the tabs described.

lllhile l have illustrated a construction which has been 'found to' be thoroughly practical and effective, I do not wish to be limited to this as it is obvious that slight changes might be made within the scope of the claims without departing from the spirit olf the invention.

I claim:

l. rlhe combination with a cassette having a back and front, oi a hollow pneumatic pad disposed on the inside tace of the back and having non-inflated port-ions extending outward beyond the hollow portion ot the pad and secured to the back.

2. The combination with a cassette liaving a bach and front, ot a hollow pneumatic pad disposed on the inside tace ot' the back and having relatively thin, non-inflated portions extending' over onto the back and secured thereto.

3. The combination with a cassette having a back and front, ot a hollow pneumatic pad disposed on the inside i'iace otl the back and having relatively thin tabs e-;tending out over the margins oit the pad and ex- -ending over onto the outer :tace oit the back and secured thereto.

4:. The combination with a cassette having a bacl; and iront, of a hollenT pneumatic pad disposed on the inside face of the back and having an area approximately the same as that ot the bacl, said pneumatic pad having non-inflated tabs extending outrard therefrom and edendin over onto the outer tace of the back, a layer of woven vtabric extending over the inside 'face ot the pad and having its margins ye):tending over said tabs and over upon the outside 'tace o't' the back, and means engaged with the outer iaee oft. the back and engaging over the felt and the tabs oi the pneumatic pad.

5. .fr cassette having a bach and front, and a hollow pneumatic pad disposed on the inside tace ot' the bacl; and attached at its margins to the haelt, the remainder ol the pad being free from attachment to the back, there being an ini'lating valve carried by the back and communicating with the cassette.

6. A cassette having a back and front, and a hollow 'pneumatic pad disposed on the inside `tace ot the back and attached at its margins to the back, the remainder olf the pad being 'tree 'trom attachment to the back7 the cassette having a nipple, the bacia of the cassette having au opening through which the nipple extends and there being an ini'iating valve connected to said nipple.

i'. is an article of manufacture, a pneumatic pad for cassettes comprising a hollow pad pr per, the margin oi'2 the pad having a plurality oi? relatively thin, flexible, non-in- .l'lated tabs eI-tonding from its sides and adapted to be -tolded over onto the outer face olf the back and engaged therewith, the central portion oi one tace of the pad being formed with a nipple whereby it may be in- Hated.

ln testimony whereof I hereunto affix my signature.

ARTHUR TN. BUCK.

l O t) lll) 

